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Do we need to occasionally run the Pentastar at wide open throttle for lubrication purposes?

Charles 236

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Running the engine long enough under enough load to heat up the exhaust is the trick - WOT won't necessarily heat it.

Interesting note that at times the 4xe will insist on running the ICE even when you have plenty of battery for electric power. I looked into it and a tech said it's to get the exhaust up to temperature, heat the cats and burn out moisture. It started the ICE and if I recall, loaded it with the generator to heat up the exhaust.
If you don't run things long enough or hot enough, it will force it on you for the good of the engine and exhaust/cats.
The 4xe uses this to burn off stale fuel and cut down on condensation in the oil. It is called FORM, I can't remember what the acronym actually stands for, but it is necessary for the ICEs fuel and oil systems continued proper functioning. Getting the exhaust up to temperature is a side benefit. You might be surprised by how often people think that their is s problem with their 4xe when it goes into FORM mode.
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ShadowsPapa

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The 4xe uses this to burn off stale fuel and cut down on condensation in the oil. It is called FORM, I can't remember what the acronym actually stands for, but it is necessary for the ICEs fuel and oil systems continued proper functioning. Getting the exhaust up to temperature is a side benefit. You might be surprised by how often people think that their is s problem with their 4xe when it goes into FORM mode.
ours has bee in FORM exactly one time - we went 1 day shy of 3 whole months without adding gas.
It will tell you when in Fuel Oil Refresh Mode
The other is just an occasional startup of the ICE, for no apparent reason, you might be driving it, or stopped. When it does that it's not in FORM and will not shut off at stop signs, and it only lasts for a while. The engine does eventually shut off, with no sign of FORM mode.

Frankly, the more I drive it and more I dig into it, the more amazing it is, and the more everything it does makes sense.

Oh, that one time - I took it to town, put in just under 10 gallons of gas and as soon as I started it, it dropped out of FORM........ poor thing wanted FRESH gas, sort of like Pickle standing by his water bowl in the morning and staring at me until I give him fresh ice water.
 

AmishMike

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I keep a brick on my pedal so I can remote start at WOT, sadly it’s capped at 3k. Can’t wait to install the borla atak twin side outs for the neighbors enjoyment! 😂😂😂😂
Tazer can fix that.
 

Darel

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The oil pump only ramps up at 3000 rpm because that's when the oil squirters kick on for piston cooling. That's the only time it needs the added volume.
 

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LOL - that's all I can say about such bunk. I can't think of where to start to shred that.

the oil pump is NOT two speed. it's variable displacement. It's driven off the crank (chain drive)
It kicks into high volume at 3,000 RPM, not 3500 rpm (right there that tells me no one knows what they are talking about - two speed? 3500 rpm?)

High RPM doesn't get "fresh oil down there". Why would that matter? the valve guides aren't pressure lubricated so oil pressure won't matter.
Pressure doesn't lubricate, oil film down. There's constantly more oil running down on things just driving it. High RPM doesn't force or push "fresh oil" anywhere.

Granny cycling? These regularly hit over 3,000 RPM.

Man, the stuff out there from supposedly business types, etc.

Basically, ignore all you've seen there.
For me, the whole first post is just plain bull crap, and the tells are the bits about how valve stems are lubricated and they say the oil pump is a two speed......
That should tell folks all the rest is made up - they don't even know how these work so how can they claim to say how to take care of them?

Well the 2 speed pump quote was made by some random dude. Maybe he meant 2 MODE which the oil pump is. But this quote:

"This engine needs occasional WOT runs if you want it to last. Granny cycling is bad for it. So bad for it we actually created a new granny cycle test during the cylinder #3 misfire issue. The highest wear is in the valve guides, because of tight valve stem seals (for emissions, reduce oil burn). They basically dry out. When you go WOT/high rpm/load you get some fresh oil in there and this keeps the wear down."

was written by a supposed former Pentastar design engineer.
 

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KevinC

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I'm curious how many of us has been past 4000 rpm? For myself, 4000 rpm sounds like a cat with his tail on fire, not sure I want to hear it scream any louder.
 

jav_eee

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I'm curious how many of us has been past 4000 rpm? For myself, 4000 rpm sounds like a cat with his tail on fire, not sure I want to hear it scream any louder.
I don’t. And living in a small city with a lot of 30mph zones and enough stop lights/signs to drive you crazy I don’t “regularly hit 3,000 rpm” either.
 

starrskream

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Tazer can fix that.
I only have 308 miles on my truck at this point. I’m not gonna put a chip on it until I’m super Duper into the three-year warranty.
In my past experience modifying the ECU in any way voids the entire warranty
 

ShadowsPapa

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I should tell about the GM design engineer who a few years back was explaining how he knew about the GM ignition systems and distributors and advance systems, specifically vacuum advance. He went on and on about what the sole purpose was how it worked and what it did - and I blew him out of the water with tech documents from the late 1930s explaining how it was designed by Chrysler, then a couple of years later, Ford adopted it, and the real true purpose. He was a "design engineer" for GM. His posts were in many Chevrolet performance forums.
There's no one person responsible for the whole thing, and you can be an engineer working on parts A and B for an engine and still not fully know what's going on with C or D.

Think of these engines that run 100,000 miles and more and rarely ever see much over 3,000 RPM let alone 4,000 RPM. Millions and millions of them out there with no ill effects.

They basically dry out. When you go WOT/high rpm/load you get some fresh oil in there and this keeps the wear down."
Sorry, still going to chuckle at that. High RPM does not furnish more oil to the valve guides directly. More splash, yes, but it's still got to get past the seals and into the guides and move down the valve stem by the up and down action of the valve itself. You have high vacuum in the intake pulling oil down the intake valve stems - WOT kills the vacuum.
High lift mode also reduces velocity out.
There's just a lot of ways all that doesn't work.
Refer back to the many millions of these engines in Grand Cherokees that never see any RPM over maybe 3500 or so.

Amazing what people search for to try to find solutions to problems that don't exist.

The oil pump only ramps up at 3000 rpm because that's when the oil squirters kick on for piston cooling. That's the only time it needs the added volume.
Unless the PUG is different, those jets are in the main gallery........ and thus oil all the time. Granted, you need MORE squirt, more oil volume at higher RPM, but.........
So you are suggesting the piston jets are turned off at below 3,000 RPM? Makes little sense as you can generate a heck of a lot of piston heat at lower RPM, high load.
 

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should tell about the GM design engineer who a few years back was explaining how he knew about the GM ignition systems and distributors and advance systems, specifically vacuum advance. He went on and on about what the sole purpose was how it worked and what it did - and I blew him out of the water with tech documents from the late 1930s explaining how it was designed by Chrysler, then a couple of years later, Ford adopted it, and the real true purpose. He was a "design engineer" for GM. His posts were in many Chevrolet performance forums.
There's no one person responsible for the whole thing, and you can be an engineer working on parts A and B for an engine and still not fully know what's going on with C or D.
Basically trust no one but ShadowPapa. Got it!
 

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Darel

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That's how I understand it. I've looked for a solenoid or something, maybe it's integral to the oil pump assembly (which has an electrical connector on it)? Or maybe a vane or reed valve that opens at 3k? I'm not saying it makes sense, but if they are trying to meet CAFE standards by reducing internal drag / resistance within the operating range the engine spends 90% of its' time, maybe? This came from a recycler on YouTube who makes videos of failed engines and disassembles them to determine cause of failure. It made a lot of sense to me. He was comparing the Pentastar to the Maserati version (side-by-side teardown) and there was a LOT of this engine that crossed between the two. Also, don't forget this engine ends up in LOTS of stuff that doesn't generate that much heat below 3k, and we can't say for sure what did and did not get badge-engineered over to the Gladiator. Maybe I should have confirmed before starting internet rumors, but like I said, it made way more sense than anything else everyone else speculates about ("dad-gum stop-start system, China be watchin' us") especially the huge difference in volume on either side of the changeover point.

Jeep Gladiator Do we need to occasionally run the Pentastar at wide open throttle for lubrication purposes? 36574ff0b8935bbd8a7724ff8b6639ee
 
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ShadowsPapa

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That's how I understand it. I've looked for a solenoid or something, maybe it's integral to the oil pump assembly (which has an electrical connector on it)? Or maybe a vane or reed valve that opens at 3k? I'm not saying it makes sense, but if they are trying to meet CAFE standards by reducing internal drag / resistance within the operating range the engine spends 90% of its' time, maybe? This came from a recycler on YouTube who makes videos of failed engines and disassembles them to determine cause of failure. It made a lot of sense to me. He was comparing the Pentastar to the Maserati version (side-by-side teardown) and there was a LOT of this engine that crossed between the two. Also, don't forget this engine ends up in LOTS of stuff that doesn't generate that much heat below 3k, and we can't say for sure what did and did not get badge-engineered over to the Gladiator. Maybe I should have confirmed before starting internet rumors, but like I said, it made way more sense than anything else everyone else speculates about ("dad-gum stop-start system, China be watchin' us") especially the huge difference in volume on either side of the changeover point.

Jeep Gladiator Do we need to occasionally run the Pentastar at wide open throttle for lubrication purposes? 36574ff0b8935bbd8a7724ff8b6639ee
The electrical connection/solenoid for the oil pump kicks it between low and high volume modes I've also looked and can't find where they shut off the nozzles, only the pump volume control.

Fact is, you don't need a whole lot of pressure. Even in the old days with far less efficient engines and oiling and oil - 10 psi/1,000 RPM was deemed plenty.
That means they guys who run 80 PSI at 5,000 RPM are wasting wear and energy (and they are the ones griping about pump drives failing!)
 

Darel

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Do you really think the squirters would be fed right off the main galley though? Path of least resistance dictates if you have one VERY VERY IMPORTANT thing that has resistance to flow(i.e. main bearings, top end) and one ancillary thing that has no resistance (i.e. squirters) wouldn't you have to have some sort of a separate feed, or a PRV or something preventing all your oil from spraying the underside of the pistons and leaving the bearings dry? I get you don't need a huge amount of oil there but you need some, you can't just turn on an open tap elsewhere on the same galley and cross your fingers.

That's why the squirter cutoff made so much sense to me. You have either a separate feed, or a PRV / reed valve that is set to, say, 50psi, that blocks them off, and that PRV would also create backpressure in the galley that kept the important bits slippery after they opened too. 3K, pump ramps up, PRV opens, squirter port opens, PRV maintains backpressure on main feed, everyone is happy.
 

ShadowsPapa

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Basically trust no one but ShadowPapa. Got it!
Over 50 years, college educated (4.0 GPA) special projects in HS engine dual fuel system designs (didn't have to take auto mechanics, had my own shop by then) and evaluated as "superior" in pattern recognition and puzzle solving by neural-psychologists (and 130 IQ)
Smart doesn't mean common sense - I'm more like Sheldon Cooper in those ways, zero social graces at all, but powers of observation, yeah.
I put things together fast.
On the other hand, there's people I tip my hat and bow to - Hootbro, among several others (actually quite a few several others if that's even a phrase)
People here have taught me a ton - priceless information.

But as far as some of these things - i've resolved issues that have baffled teams of "experts". I've solved network issues a whole section of IT people couldn't resolve over several months, and i've fixed issues with the network at Compressor Controls where "certified network engineers" didn't find. (and got my boss fired in the process, sorry to say)

I don't know it all - but you really have to watch what you see or read or watch on the internet.

The GM engineer swore - and others supported the guy, yeah, he knows, he's a GM engineer!, that the vacuum advance was only for emissions control and as such is best off connected to manifold vacuum. He swore it was a GM thing and was only for those reasons.
I produced patent information, photos of like new 1940s Fords with vacuum advance, the technical documents and proof that it should connect to ported vacuum.
For that I was endlessly flamed, it was unreal. How DARE I question a GM engineer!! You just don't do it.
To this day, 10 years later, some guys are still pissed at me for daring to demonstrate that their emperor had no clothes.

Believe whatever or whoever you want, I don't really care, my life is a lot bigger than that. My thing is fighting the old internet lore out there that is "fact" because it gets repeated 100 times in many places and no one has dared to question it.
It really won't matter to me how you drive YOUR vehicles - my thing is let's fight some of this questionable stuff out there.
BTW - what's the "cylinder 3 misfire" thing they talk about?
If that's the prior gen 3.6, then they are also talking the other 3.6, not this one.
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